Ovarian programming of gamete progression and maturation in the female genital tract

Whilst the rate of displacement and migration of sperm cells in the female reproductive tract of rodents, farm animals and humans has attracted attention for at least 50 years, the overriding purpose of sperm transport has not always been kept in focus. This report is concerned with spermatozoa that can penetrate the egg investments and promote formation of a zygote, judgements involving a surgical approach and subsequent phase-contrast microscopy. A minimum period of 6–8 hours was required for such spermatozoa to be established in the oviducts in sheep and cows mated at the onset of oestrus. Sperm were then arrested in the caudal 12 cm of the isthmus for 17–18 hours or more until just before the moment of ovulation, when they were activated and displaced onwards to the site of fertilization at the ampullary-isthmic junction. The time-scale of these events differs in pigs as a result of the intra-uterine site of ejaculation and the 40-hour interval between the onset of oestrus and ovulation, but the pre-ovulatory sequestering of viable spermatozoa in the caudal tip of the oviduct is conspicuous for 36 hours or more. This function of the oviduct appears to be under local control from ovarian follicular hormones and, as judged by sperm motility and membranous changes, so does the process of capacitation. Completion of capacitation is interpreted as a peri-ovulatory event.     

Effect of secretions from female genital tract on some vitality indexes of spermatozoa]

The survival time and speed of movement of washed bull spermatozoa suspended in Peterson buffer (1:10) and secretions from various parts of the genital tracts of cows (Cervix, horns, oviductus) collected in different stages of the estrous cycle (early luteal, full luteal, follicular) were determined. Survival time of the spermatozoa was determined at 46.5 degrees under a microscopic using the Beck and Salisbury method. The speed of movement was measured at 37 degrees in a Burker hemocytometer. The survival time and speed of movement of the spermatozoa were stimulated by secretions in the follicular and early luteal stages. Secretions during the full luteal stage depressed these figures. Secretions taken from different parts of the genital tract did not show any significant differences in stimulatory action.     

Distribution of carnitine and acylcarnitine in the hamster epididymis and in epididymal spermatozoa during maturation

The highest levels of carnitine and acylcarnitine were found in the cauda epididymidis, and spermatozoa from the cauda contained greater amounts of total carnitine (free carnitine plus acylcarnitine) than those removed from the corpus or caput epididymidis. Spermatozoa from the distal cauda contained significantly greater amounts of both free and total carnitine than those removed from the proximal cauda epididymidis. The acylcarnitine:carnitine ratio was 1.7 and 0.37 in caput and cauda spermatozoa, respectively and 1.7 and 1.3 in caput and cauda fluid, respectively. It is suggested that the accumulation of carnitine is involved in sperm maturation and that acylcarnitine serves as an energy substrate for epididymal spermatozoa.     

女性生殖道微生态屏障

随着感染微生态学的发展,尤其是宿主-微生物相互作用的研究深入,越来越多的研究发现,新的微生态屏障在维持宿主健康方面发挥着重要作用。微生态屏障包括微生物屏障,机械屏障,免疫屏障和化学屏障四个部分。其中机械屏障是微生态屏障的基础,微生物屏障是微生态屏障的关键,免疫屏障是微生态屏障的核心,化学屏障是微生态屏障的有机组成部分。微生态屏障可维持宿主生境的微生态平衡,防止病原微生物的入侵和感染的发生。     

Intramitochondrial transformations during oocyte maturation in the mouse

An electron microscope study of oocyte maturation in the mouse revealed that some mitochondria undergo gradual transformation in their ultrastructural appearance. In very young oocytes these mitochondria were already found to contain vacuoles, one in each such organelle. In somewhat older oocytes more mitochondria displayed vacuoles which generally appeared to be getting larger. These intramitochondrial vacuoles were found to be essentially optically empty structures surrounded by a single membrane. In favorable sections someof the developing vacuoles had a bottle-shaped appearance, the constricted end of which was attached to the inner limiting membrane of the mitochondrion. With further maturation of the oocytes vacuoles having a pear-shaped appearance became evident. An hypothesis was presented outlining the mode of formation of these vacuoles by expansion of the individual cristae. Intramitochondrial transformations occuring during both oogenesis and spermatogenesis in mammals were reviewed.     

Immunological responses to semen in the female genital tract

When spermatozoa, seminal plasma and semen extender reach the uterus and interact with local leukocytes and endometrial cells, several immune mechanisms are initiated which have immediate, mid-term and long-term effects on ovulation, sperm cell selection, fertilization and pregnancy success by assuring the acceptance of fetal tissues. This report gives an overview on relevant key immune mechanisms following roughly the time axis after insemination. Detailed knowledge regarding these mechanisms will aid maximizing reproductive efficiency in livestock production. In the future, the many species involved will require a more comparative approach, since evidence is growing that endometrial physiology and the response to varying amounts and compositions of seminal plasma, various semen extenders, and variable numbers of spermatozoa also provoke different immune responses.     

Group B streptococci in the female genital tract.

Vaginal carriage rates of group B streptococci among 250 women attending a clinic for sexually transmitted diseases, 123 attending family planning clinics, and 110 in labour wages were 36.0%, 17-1% and 6.4% respectively. The presence of group B streptococci was not associated with a vaginal discharge or the use of oral contraceptives in the non-pregnant women, or with the isolation of Neisseria gonorrhoeae or Trichomonas vaginalis from the women attending the clinic for sexually transmitted diseases. Serotyping showed a predominance of types II and III in non-pregnant women and an overall incidence of non-typable strains of 14.8%. There was no relationship between serotype and antibacterial susceptibility.